Restoration of a Byzantine settlement in Mystras, Peloponnese (picture taken in 2002).

Mystras (also Mistra, Mystra and MistrasGreek: Μυστράς , Μυζηθράς Mizithras or Myzithras in the chronicle of Morea
) was a fortified town in Morea (the Peloponnesus), on Mt. Taygetos, near ancient Sparta. It lies approximately eight kilometres west of the modern town of Sparti.

The Latin despotate was retaken in 1262 by Michael VIII Palaeologus after the recapture of Constantinople in 1261, when John Palaeologus, Michael's brother, ransomed William to the other Latin princes. It remained the capital of the despotate of Morea, ruled by relatives of the Byzantine emperor, although the Venetians still controlled the coast and the islands. Mystras and the rest of Morea became relatively prosperous after 1261, compared to the rest of the empire. Under the despot Theodore it became the second most important city in the empire after Constantinople, and William II's palace became the second residence of the emperors.

The last Byzantine emperor, Constantine XI, was despot at Mystras before he came to the throne. Demetrius, the last despot of Morea, surrendered the city to the Ottoman emperor Mehmed II in 1460. The Venetians occupied it from 1687 to 1715, but otherwise the Ottomans held it until 1832, when it was abandoned by King Otto for the newly rebuilt Sparta.

In 1989 the ruins, including the fortress, palace, churches, and monasteries, were named a UNESCO World Heritage Site.